The term "insulator" is used to mean any insulating casing designed to contain electrical equipment, such as a circuit-breaker for example.
It is known that such an insulator may comprise a cylindrical casing made of epoxy resin and provided with annular fins made of silicone.
Unfortunately, epoxy resin deteriorates rapidly when it is exposed to atmospheric conditions. Such insulators therefore have particularly limited life spans because they deteriorate rapidly under the effect of inclement weather.
Furthermore, silicone is a particularly expensive material.